Visual measuring device for bending machine



p 2, 1969 G. F. BECKWELL 3,464,247

VISUAL MEASURING DEVICE FOR BENDING MACHINE Filed May 18, 1967 2 Sheets-Sheet 1 if; 29 i Sept. 2, 1969 G. F. BECKWELL 3,464,247

VISUAL MEASURING DEVICE FOR SENDING MACHINE Filed May 18, 1967 2 Sheets-Sheet 2 Jag 3 m W d0 23w W; 16 14 'W 25 INVENTOR.

-vita-5L United States Patent 3,464,247 VISUAL MEASURING DEVICE FOR BENDING MACHINE George F. Beckwell, Aurora, 11]., assignor to Pines Engrneering Co., Inc., Aurora, 111., a corporation of Illinois Filed May 18, 1967, Ser. No. 639,517 Int. Cl. B21d 7/14; G01c 9/04, /26

U.S. Cl. 7237 11 Claims ABSTRACT OF THE DISCLOSURE Apparatus for measuring the radius, plane and angle of a bend being performed in a piece of tubular stock which includes a pair of image projectors adapted to project enlarged images representative of the radius, plane and angle of a bend in the stock onto guide charts for visual observation.

The invention relates to improvements in the construction and assembly of novel means for affording a visual pattern of the angle, plane and radius of a bend performed in tubular stock while the bend is being generated by a bending machine of a type that re-rolls or extrudes the tubular stock.

The improved apparatus is used in association with or mounted on a bending machine of the character that has rollers or other means therein operable to work on a length of tubular stock, as it is fed therethrough slowly, so as to generate a uniform bend at a desired plane, angle and radius. Such machines are used particularly for bending tubular stock of considerable diameter. During the forming operation the stock is bent so that its finished projecting end is carried out of the plane of its longitudinal axis in an upwardly curved arc of the desired radius. There is room for error in the bending process which results in the bend not maintaining its required uniform radius or in not bending in the correct angle or plane. Such mal-function is frequently not observed until after a bend is completed.

The apparatus of the present invention affords visual means, on an enlarged scale, whereby the bend being generated is constantly under surveillance and any deviation from the intended bend is immediately observed and can be corrected promptly by proper adjustment of the bending machine tools.

More specifically, the present invention comprises the mounting on the bending machine of novel light-beam projection means operably connected with the length of stock being bent in such a-manner that should the bending radius departfrom that intended, even to the slightest degree, the position of the light beam, as projected on a control chart, is varied. The assembly also includes second light-beam projection means that is operably connected with the length of stock being bent in such a manner that should the bend depart from its intended plane, the position of the light beam, as projected on a second control chart, is varied. This assembly also affords positive indication of the angle of the bend being performed. When any departure from the norms of the angle of bend, the radius of bend or the plane of the bend occurs it is immediately evidenced on the control charts and may be corrected by adjustment of the bending machine controls.

It is, therefore, an object of the invention to provide apparatus of the character referred to.

Another object is to provide, in a bending machine, means to visually determine the specific characteristics of the bend being performed on a length of stock.

Another object of the invention is to provide novel light beam projection means.

Patented Sept. 2, 1969 Another object is to provide novel means operable in response to the bending of a length of stock for visually indicating the radius of the bend.

Another object is to provide novel means, operably associated with a length of stock while being bent, for visually recording the degree of bend and the plane of the bend.

Another object is to provide, in a bending machine, novel means for visually recording bend characteristics of a piece of stock worked in the machine, which means is not expensive or difficult to manufacture, is positive and accurate in its operation, is entirely automatic in operation, is simple to use and is efiicient in use.

The structure by means of which the above noted and other objects and advantages of the invention are at tained will be described in the following specification, taken in conjunction with the accompanying drawings, showing a preferred illustrative embodiment of the invention, in which:

FIG. 1 is a side elevational view of a bending machine, showing the recording mechanisms mounted on the machine and associated with the workpiece;

FIG. 2 is a front elevational view of the apparatus for recording the angle and plane of the bend, as viewed along line 2-2 of FIG. 1;

FIG. 3 is a detail sectional view of the lens assembly, taken substantially on line 33 of FIG. 2;

FIG. 4 is a view, on a reduced scale, of the target used in association with the angle and plane-of-bend indicating apparatus;

FIG. 5 is a front elevational view of the apparatus for indicating the radius of bend, as viewed along line 5-5 of FIG. 1;

FIG. 6 is a top plan view of the apparatus shown in FIG. 5, taken substantially on line 6-6 of FIG. 5;

FIG. 7 is a transverse sectional view of the apparatus, taken on line 77 of FIG. 6; and,

FIG. 8 is a view, on a reduced scale, of the target used in association with the apparatus of FIG. 5.

Referring to the exemplary disclosure of the invention as best shown in FIG. 1 of the accompanying drawings, the novel visual control apparatus is carried, in part, on the bending machine 11 and, in part, on the length of stock 12 being bent by the machine. Machines of this character are designed to perform a bend in tubular and like stock of considerable diameter by' the well known re-roll or extruded method. In such machines, the generation of the bend takes place gradually as the length of stock is slowly advanced between the bending tools covered until the bending operation has been completed,

whereupon the bent stock must be re-worked or discarded. The devices of the present invention afford visual patterns by means of which the angle, the plane and the radius of the bend are indicated on an enlarged scale at all times on control charts or targets, so that should there be any deviation from the norms, however slight, such deviation can be corrected immediately by readjustment of the bending tools. Such visual patterns are generated by means of projection assemblies 14 and 15. The assembly 14 is carried directly on the machine frame and it is designed to indicate the radius of the bend. The assembly 15 is attached to the lead end of the stock 12 being bent and it is designed to indicate the angle and the plane of the bend being generated.

The assembly 14, best shown in FIGS. 1 and 5 to 7, 1s carried in a mounting bracket 16 that is mounted for vertical adjustment on a rigid upright 17 supported by the machine frame 11. A measuring tape 18 is attached at one end to the machine frame and at its other end to said mounting bracket to facilitate accurate positioning of the bracket vertically in conformance to the intended radius of bend to be performed in the tubular stock. A longitudinally disposed frame 19 is slidable in said bracket 16, in a direction normal to the axis of the tubular stock 12, and which frame carries on one end a spring-loaded reel 20 having a cable 21 wound thereon. The other end of the frame 19 mounts a sheave 22 (FIG. 6) around which the cable is trained. The cable is then passed freely through an eyelet 23 in said frame end which is located in vertical alignment with the bending tools in the machine and with the longitudinal axis of the tubular stock 12. The end of the cable leaving said eyelet is carried downwardly and forwardly, and is secured, as by a clamp strap 24, to the tubular stock 12.

The frame 19 has a horizontal flange 25 on its forwardly disposed side upon which is seated the front end of a plate 26, which is pivoted thereto, as at 27. This plate mounts firmly a housing 28 containing a light source and a collector lens assembly 29 having a vertical index line 31 on its lens surface. The rear or free end of the plate 26 is detachably connected to the cable 21 which extends beneath it, as by a clamp 32.

It should be evident that any movement of the cable 21, which is retained taut at all times by the springloaded reel 20, is imparted to the light housing 28 so as to cause the same to pivot about its plate mounting, at 27, and thereby alter the direction, in a horizontal plane, of the light beam 33 projected through the lens assembly.

This light beam and the image 31a of the vertical index line 31 are projected onto a large control chart or target 34 supported on a vertical surface in front of the assembly. As best shown in FIG. 8, the control chart has a vertical base line 35 thereon over which is initially laid the enlarged image 31a of the index line 31 of the lens assembly. Obviously, any variation in the angle of the projected light beam, resulting from swinging of the light housing 28 will carry the image 31a of the index line 31 to one side or the other of base line 35.

Because the cable 21 is trained or held at its top end on the vertical axis of the bending tools, as at eyelet 23, the length of its portion extending from said point of its attachment to the tubular stock will not vary so long as a true radius of bend is being maintained. However, should the radius of bend increase or decrease during the bending operation, the length of said cable portion will correspondingly increase or decrease with resultant pivoting of the light housing 28 and misalignment of the projected image 31a. The chart 34 may carry a degreecalibrated horizontal line 36 for the purpose of visually indicating the degree to which the image has varied. Should any variation occur, the usual controls for the bending tools can be immediately adjusted to correct malfunction so as to return the image 31a to registration with the vertical base line 35.

The assembly 15, best shown in FIGS. 1, 2 and 3, is mounted directly on the lead end of the tubular stock, preferably by means of a block 37 that is secured thereto and on the top side thereof as by a clamp strap 38. Projecting laterally from one side of the block is a rigid rod 39 that mounts firmly a transparent protractor disc 41. Also mounted for free rotation on said rod is a substantially rectangular frame 42 having a counterweight 43 depending therefrom.

Mounted within the frame 42 is a lamp housing 44 having its lens 45 directed toward the transparent protractor 41. A lens assembly 46 is also carried in the frame on the other side of the protractor and this assembly has a light entrance aperture 47 in registering alignment with the lamp housing lens 45. The lens assembly 46 is substantially tubular as shown in FIG. 3, and is arranged with its axis at right angles to the frame and has a collector lens 46a on each end. Arranged within the tubular lens assembly, inwardly of the beam receiving aperture, is a prism 48. This prism is preferably pivotally mounted so as to be positioned to direct light entering aperture 47 toward either one of the lenses 46a. Such reverse of the prism is desired so as to permit the assembly 15 to be mounted on either the right or the left side of the 'mbular stock in a manner to cause the light beam to be projected forwardly away from the machine housing and onto a control chart or target 49 that is carried on a vertical surface. In use, an image of the protractor calibration reading aligned with the light beam is projected onto the control chart.

As best shown in FIG. 4, this chart 49 has a vertical base line 51 with degree markings and an intersecting horizontal base line 52 also with degree markings. Prior to bending of the tubular stock the protractor degree image 41a is placed in register with the vertical base line. As the bending proceeds, the image, which is always projected in a horizontal plane due to the gravity control of frame 42, will progressively advance up the vertical base line. Should there be any deviation from the intended plane of the bend, the image 41a will move to the right or left of said vertical base line 51. The degree of such displacement can be ascertained by reference to the degree markings on the horizontal base line 52. Adjustment of the bending tools may then be attended to compensate for the deviation and return the image to the vertical base line. The amount of bend in the tubular stock at any given moment is indicated by reference to the degree markings on the vertical base line 51. Thus, when a bend of a given degree is required, say 35, the bending operation will be stopped when the image reaches the 35 index on the vertical base line.

It should be evident at this time that the bending operation is under control of the operator at all times. By simply observing the location of the enlarged images on the two control charts, the operator instantly is apprised of the exact status of the bend being produced. Also, in instances when helical bends, compound radius, spiral or other bend configurations are required, base lines on the charts can be generated to represent such bends and the machine adjusted periodically to produce the required variation from a straight line bend.

Although I have described a preferred embodiment of the invention, in considerable detail, it will be understood that the description thereof is intended to be illustrative, rather than restrictive, as many details of the structure disclosed may be modified or changed without departing from. the spirit or scope of the invention. Accordingly, I

do not desire to be restricted to the exact construction described.

I claim:

1. In a machine for bending tubular and like stock which includes a frame carrying tube bending tools, wherein the improvement comprises, mounting in assoclation with said frame and with the tubular stock of means capable of projecting images representative of the radius, angle and plane of the bend being performed in said stock.

2. The machine recited in claim 1, in which there are two image projection means.

3. The machine recited in claim 2, in which one of sa1d means is mounted on the machine and the other is carried by the stock.

4. The machine recited in claim 2, in which one of sa1d means is mounted on the machine and is operably connected with the stock to project an image representative of the radius of bend and the other one of said means is mounted directly on the stock to project an image representative of the degree and plane of the bend.

5. The machine recited in claim 2, in which one of said means is spring-controlled and the other is gravity controlled.

6. The machine recited in claim 2, in which a cali- 5 brated chart is associated with each image projection means each to receive an image projected thereon.

7. Apparatus for measuring the radius of bend being performed in a piece of stock which comprises a vertically adjustable frame, an image projector carried by said frame, and means connecting said image projector with the piece of stock operable in response to variations in the radius of bend to alter the direction in which the image is projected.

8. The apparatus recited in claim 7, in which the image projector is pivotally mounted on a vertical axis on said frame.

9. The apparatus recited in claim 7, in which the means connecting the image projector with the stock comprises a cable.

10. Apparatus for measuring the angle and plane of bend being performed in a piece of stock which comprises, a frame pivotally mounted on a horizontal axis on said stock, an image projector carried by said frame and adapted to project an image in a horizontal plane, and a protractor associated with said image projector and through which alight beam is projected.

11. The apparatus recited in claim 10, in which the protractor is carried firmly by said stock.

US. Cl. X.R. 

